The mission ofthe Protein Structure Laboratory (PSL) is to provide investigators with state-of-the-art instrumentation, facilities, and expertise for all aspects of protein crystallography. This includes protein crystallization. X-ray data collection, data analysis, structure solution and refinement, and structure analysis. Laboratory staff provides advice and consultation, training, access to facilities for experienced crystallographers, and a range of services from crystal growth to structure solution and refinement, and preparation of materials for publications and grant submissions. In addition, the PSL provides training to students, post-docs and faculty who wish to learn any or all aspects of protein structure determination. To facilitate this, modern crystallization methods, in-house or synchrotron X-ray diffraction data collection, and the most recent crystallographic software are utilized. The staff consists of one experienced full time Ph.D. crystallographer. Dr. Scott Lovell, who serves as the Director ofthe Laboratory, and a Research Assistant to assist with crystallization screening and sample preparation for X-ray diffraction experiments. The PSL is located in close proximity to other core service laboratories in the University of Kansas Structural Biology Center building. During Phase II, the PSL has collaborated with 36 investigators from academic, government and industrial institutions. This has resulted in more than 100 structures delivered, 64 deposited to the Protein Databank, 26 publications and 17 grant applications submitted in which the PSL staff were listed. The PSL will continue to expand the base of collaborators and provide high-level facilities, expertise and training during Phase III ofthe COBRE-PSF.